keep in suspense
keep (one) in suspense
To cause one to remain in a state of anxious apprehension. Well, don't keep me in suspense—tell me what happened next! The TV show kept audiences in suspense with a big cliffhanger at the end of the season finale.
keep someone in (a state of) suspense
to make someone wait anxiously for something. Tell us what happened. Don't keep us in a state of suspense. Don't keep me in suspense!