Cal. Civ. Proc. Code § 527

(a) A preliminary injunction may be granted at any time before judgment upon a verified complaint, or upon affidavits if the complaint in the one case, or the affidavits in the other, show satisfactorily that sufficient grounds exist therefor. No preliminary injunction shall be granted without notice to the opposing party.
(b) A temporary restraining order or a preliminary injunction, or both, may be granted in a class action, in which one or more of the parties sues or defends for the benefit of numerous parties upon the same grounds as in other actions, whether or not the class has been certified.
(c) No temporary restraining order shall be granted without notice to the opposing party, unless both of the following requirements are satisfied:
1. (1) It appears from facts shown by affidavit or by the verified complaint that great or irreparable injury will result to the applicant before the matter can be heard on notice.
2. (2) The applicant or the applicant’s attorney certifies one of the following to the court under oath:
  1. (A) That within a reasonable time prior to the application the applicant informed the opposing party or the opposing party’s attorney at what time and where the application would be made.
  2. (B) That the applicant in good faith attempted but was unable to inform the opposing party and the opposing party’s attorney, specifying the efforts made to contact them.
  3. (C) That for reasons specified the applicant should not be required to so inform the opposing party or the opposing party’s attorney.
(d) In case a temporary restraining order is granted without notice in the contingency specified in subdivision (c):
1. (1) The matter shall be made returnable on an order requiring cause to be shown why a preliminary injunction should not be granted, on the earliest day that the business of the court will admit of, but not later than 15 days or, if good cause appears to the court, 22 days from the date the temporary restraining order is issued.
2. (2) The party who obtained the temporary restraining order shall, within five days from the date the temporary restraining order is issued or two days prior to the hearing, whichever is earlier, serve on the opposing party a copy of the complaint if not previously served, the order to show cause stating the date, time, and place of the hearing, any affidavits to be used in the application, and a copy of the points and authorities in support of the application. The court may for good cause, on motion of the applicant or on its own motion, shorten the time required by this paragraph for service on the opposing party.
3. (3) When the matter first comes up for hearing, if the party who obtained the temporary restraining order is not ready to proceed, or if the party has failed to effect service as required by paragraph (2), the court shall dissolve the temporary restraining order.
4. (4) The opposing party is entitled to one continuance for a reasonable period of not less than 15 days or any shorter period requested by the opposing party, to enable the opposing party to meet the application for a preliminary injunction. If the opposing party obtains a continuance under this paragraph, the temporary restraining order shall remain in effect until the date of the continued hearing.
5. (5) Upon the filing of an affidavit by the applicant that the opposing party could not be served within the time required by paragraph (2), the court may reissue any temporary restraining order previously issued. The reissued order shall be made returnable as provided by paragraph (1), with the time for hearing measured from the date of reissuance. No fee shall be charged for reissuing the order.
(e) The opposing party may, in response to an order to show cause, present affidavits relating to the granting of the preliminary injunction, and if the affidavits are served on the applicant at least two days prior to the hearing, the applicant shall not be entitled to any continuance on account thereof. On the day the order is made returnable, the hearing shall take precedence over all other matters on the calendar of the day, except older matters of the same character, and matters to which special precedence may be given by law. When the cause is at issue it shall be set for trial at the earliest possible date and shall take precedence over all other cases, except older matters of the same character, and matters to which special precedence may be given by law.
(f) Notwithstanding failure to satisfy the time requirements of this section, the court may nonetheless hear the order to show cause why a preliminary injunction should not be granted if the moving and supporting papers are served within the time required by Section 1005 and one of the following conditions is satisfied:
1. (1) The order to show cause is issued without a temporary restraining order.
2. (2) The order to show cause is issued with a temporary restraining order, but is either not set for hearing within the time required by paragraph (1) of subdivision (d), or the party who obtained the temporary restraining order fails to effect service within the time required by paragraph (2) of subdivision (d).
(g) This section does not apply to an order issued under the Family Code.
(h) As used in this section:
1. (1) “Complaint” means a complaint or a cross-complaint.
2. (2) “Court” means the court in which the action is pending.