This is a randomized (study medication assigned to participants by chance), placebo- and positive-controlled, double-blind (Periods 1 to 3), and open-label (Period 4), single-dose, crossover study in up to 60 healthy adults. The study has a Screening Phase and a Treatment Phase. Participants will be randomly assigned to 1 of 6 treatment sequence groups and will receive the 4 treatments (1 treatment per period); Treatment A (intravenous placebo, Intranasal placebo and Oral placebo tablet matched to the moxifloxacin tablet), Treatment B (intravenous placebo, 84 milligram (mg) of intranasal esketamine as 4 devices, each with 28 mg esketamine and Oral placebo tablet matched to the moxifloxacin tablet), Treatment C (intravenous placebo, Intranasal placebo and 400 mg oral moxifloxacin tablet) and Treatment D (0.8 milligram per kilogram of intravenous esketamine, Intranasal placebo and Oral placebo tablet matched to the moxifloxacin tablet ). The first 3 periods will be double-blinded and the fourth period will be open-label. Periods 1, 2, 3, and 4 will be separated by 5 to 7 days. Primarily the effects of esketamine on QT/QTc intervals and electrocardiogram (ECG) morphology will be evaluated. Safety of the participants will be monitored throughout the study.